Problem: Multiply, reduce to lowest terms, and write as a mixed number: $ 3\dfrac{4}{5} \times 5\dfrac{3}{4} $
Answer: $ = \dfrac{19}{5} \times \dfrac{23}{4}$ $ = \dfrac{19 \times 23}{5 \times 4}$ $ = \dfrac{437}{20}$ $ = 21 \dfrac{17}{20}$